Skip Navigation Bar

Fact Sheet
The National Library of Medicine

The National Library of Medicine (NLM), in Bethesda, Maryland, is a part of the National Institutes of Health, US Department of Health and Human Services (HHS). Since its founding in 1836, NLM has played a pivotal role in information innovation, and in translating biomedical research into practice to improve the public health.

NLM is the world's largest biomedical library and the developer of electronic information services that deliver trillions of bytes of data to millions of scientists, health professionals and members of the public around the globe, every day. Anyone can search or download free information directly from the NLM website, find it via a search engine, or use an “app” that provides value-added access. External computer systems use NLM applications programming interfaces to obtain NLM data for commercial products and in research. NLM is one of the Federal government’s largest providers of digital content, dispatching an average of more than 6,500 million bits of data per second.

The Library is open to all and has many services and resources. Its digital and physical collections include books, journals, manuscripts, images, and multimedia; genomic, chemical, toxicological, and environmental data; drug information; clinical trials data; health data standards; software; and consumer health information.

In today's increasingly digital world, NLM carries out its mission of enabling biomedical research, supporting health care and public health, and promoting healthy behavior by:

  • Acquiring, organizing, and preserving the world's scholarly biomedical literature;
  • Providing access to biomedical and health information across the country in partnership with the 6,400-member National Network of Libraries of Medicine (NN/LM®);
  • Serving as a leading global resource for building, curating and providing sophisticated access to molecular biology and genomic information, including those from the Human Genome Project and NIH Common Fund;
  • Creating high quality information services relevant to toxicology and environmental health, health services research, and public health;
  • Conducting research and development on biomedical communications systems, methods, technologies, and networks and information dissemination and utilization among health professionals, patients, and the general public;
  • Applying Big Data and technology to improve health, analyzing the immense quantities of scientific data available from NLM and other sources, including multiple sources of de-identified prescription and patient outcome data, and applying deep knowledge of clinical terminology and natural language processing, as well as the Library’s rich terminology resources and tools;
  • Funding advanced research in biomedical informatics and data science; and
  • Supporting training and career development, including pre- and post-doctoral research training in biomedical informatics and data science, and specialized training for librarians.

NLM Organization

The NLM organizational structure consists of the Office of the Director and six major operating components. These are:

Scientific Information Services

The most frequently consulted online scientific medical resource in the world is MEDLINE®/PubMed®, a publicly available database of more than 26 million journal citations mainlyfrom 1946 to the present.

Another important part of the Library’s vast online holdings is PubMed Central® (PMC), a web-based repository of biomedical journal literature providing free, unrestricted access to 4 million full-text articles. Since 2005, PMC has also been the designated repository for papers submitted in accordance with the NIH Public Access Policy.

NLM also distributes GenBank®, a collection of all publicly available DNA sequences built in collaboration with international partners in Europe and Japan, and also provides access to the assembled Human Genome data.

It has been more than two decades since the Visible Human Project® male and female datasets were released. The datasets (some 50 gigabytes in all) are being applied in a wide range of imaginative projects by more than 3,750 licensees in 64 countries.

The Library offers a wide range of resources relating to minority health and health disparities, HIV/AIDS, disaster and public health emergencies, and environmental health and toxicology. Among the best known are TOXNET®, AIDSinfo, and DisasterLit.

The field of precision medicine holds great promise. The acquisition and use of new knowledge about the health effects of an individual’s genetic makeup, environmental exposures, and lifestyle choices and constraints are necessary prerequisites to precision medicine. NLM supports both the acquisition and the direct clinical application of such knowledge. The Database of Genotypes and Phenotypes (dbGaP) includes the results of more than 600 studies of the interaction between genetic makeup and observable traits (high blood pressure, for example) associated with many diseases, such as cancers, heart disease, and autism. The ClinVar database makes knowledge about the clinical significance of genetic variations available, as it is determined by scientists. And the Genetic Testing Registry provides detailed information about genetic tests that are available for clinical and research use.

Information Services for the Public

The Library has extensive information resources to serve the general public. The Library's main portal for consumer health information is MedlinePlus®, available in both English and Spanish (MedlinePlus en español). MedlinePlus has comprehensive, up-to-date, easy-to-read information on nearly 1,000 health topics. It also provides videos, health news, a dictionary and medical encyclopedia. MedlinePlus features information on thousands of prescription and over-the-counter medicines, as well as alternative treatments such as herbs and supplements. And, to provide the public with more health care news it can use, NLM staff oversees the production of the free, quarterly NIH MedlinePlus magazine and its Spanish-language counterpart, NIH MedlinePlus Salud. Through MedlinePlus Connect, patients and health care providers access targeted information at the point they need it in an electronic health record system. is the world’s largest registry and results database of clinical studies. Visitors to the site, including patients, medical journal editors, and healthcare professionals, can access information on over 228,000 ongoing and completed studies with locations in all 50 states and in 191 countries. Sponsors of studies available on include NIH and other US government agencies, pharmaceutical companies, academic institutions, and international organizations.

Genetics Home Reference is the NLM website for consumer information about genetic conditions and the genes or chromosomes associated with those conditions. This information resource bridges consumer health information and scientific bioinformatics data, and it links to many existing high-quality resources. Genetics Home Reference covers more than 1,100 genetic conditions and more than 1,300 genes. Topics are added and updated on a regular basis and reviewed by experts in human genetics.

NLM has information for the public, too, on toxicology, environmental health, and HIV/AIDS. The Household Products Database, provides easy-to-understand data in consumer-friendly language on the potential health effects of more than 4,000 ingredients contained in more than 16,000 common household products. Tox Town® points out many harmful substances and environmental hazards not only in a town but in a port, a big city, a farm, US border regions and the American Southwest. The Library has also created a series of information portals targeted to special populations, including Native Americans, and those living in the Arctic.

The Student Environmental Health Portal contains topical information tied to national science standards and includes videos, games, lesson plans and factual information suitable for use in the classroom.

National Network of Libraries of Medicine

The Library’s key partner in making information available is the National Network of Libraries of Medicine (NN/LM). The network consists of 6,400 member institutions, supported via eight regional offices under contract to the National Library of Medicine. The mission of the NN/LM is to advance the progress of medicine and improve the public health by providing all US health professionals with equal access to biomedical information and improving the public's access to information to enable them to make informed decisions about their health.

Grant Programs

The National Library of Medicine offers grants for research projects, research training and career development in biomedical informatics and data science. Biomedical informatics research applies computer and information sciences approaches to improve the representation, management, analysis, integration, dissemination and use of biomedical data and knowledge. Research grants focus on novel methods and techniques for intelligent systems, natural language understanding, support for health decisions, computational modeling, in silico discovery and other advanced topics relating to clinical care, public health, translational bioinformatics, consumer health, and basic biomedical information sciences including social and behavioral sciences. In addition, NLM offers several unique resource grant programs that support improving access to scholarly works and information resources to reduce health disparities, as well as small business grants.

Annual Statistical Profile of NLM (Fiscal Year 2015)

  • Collection (book and nonbook) – 27,846,111
  • Items cataloged – 24,897
  • Active serial subscriptions – 17,556
  • Articles indexed for MEDLINE – 806,326
  • Circulation requests processed – 309,817
  • For interlibrary loan – 180,733
  • For on-site users – 129,084
  • Computerized searches (MEDLINE/PubMed) – 2,796,260,949
  • Budget authority – $337 M
  • Staff – 1,741

Address: 8600 Rockville Pike, Bethesda, MD 20894

Phone (Toll-Free): 888.FIND.NLM (888.346.3656)

Visitor Information: //

Tours: Join us any Monday-Friday (except Federal holidays) from 1:30-2:30 PM for informative and interactive walking tours. Tours begin in the NLM Visitor Center, off the first floor lobby of Bldg. 38A, Lister Hill Center. Walk-ins welcome. To schedule group tours, please call 301.827.6479.

Reading Room Hours: Monday-Friday, 8:30 AM-5:00 PM (except Federal holidays).

Holiday Closings: // 

For more information about NLM programs, contact the Office of Communications and Public Liaison (mailing address above),, 301.496.6308, or consult the NLM website.